Luminaire with emergency lighting function

According to one embodiment, a luminaire includes a dim lighting circuit, an emergency unit, a dimming-signal input section, and a dimming control circuit. The dim lighting circuit dimly lights a light source at a dimming ratio corresponding to a dimming signal. The emergency unit includes a charging circuit for charging a battery with an external power supply in a normal time and supplies a power supply of the battery to the dim lighting circuit in an emergency. The dimming-signal input section receives the input of the dimming signal from the outside. The dimming control circuit gives the dimming signal input from the dimming-signal input section to the dim lighting circuit in a normal time and gives a dimming signal having a dimming ratio for an emergency to the dim lighting circuit in an emergency.